1. Field of the Invention
The present invention relates to a socket assembly, and more particularly, to a socket assembly for use with included an insulated reinforced plate having a printed circuit board sandwiched therebetween
2. Description of the Related Art
Present computer usually has a high speed and double data transmission rate and continually works for a long time. As a result, a powerful CPU (Center Process Unit) of the computer brings up more and more heat. Therefore a heat sink is required to dissipate the heat during a normal work of the computer. When such a heat sink including a plurality of metal fins is mounted on top of a socket, which is mounted on a PCB and adapted to electrically interconnect the CPU and the PCB. Since the PCB can not endure so heavy weigh, a backplane is assembled on a bottom surface of the PCB to strengthen the PCB. In the existing application, the heat sink is locked to a so called retention module (RM) which is bolted onto the PCB. In addition, the socket assembly includes a stiffener which is bolted to a reinforced backplane disposed on the underside of the PCB. In order to effectively dissipate heat from the CPU, the heat sink must press hardly against to a top surface of the CPU. Inevitably, the spring load will also are transferred to the CPU and the socket on which the CPU is mounted. As a result, the backplane mentioned plays a vital role in this application.)
Commonly, typical backplanes include two types, one is configured by plastic, another is formed by metal. The plastic backplane has a simple manufacture process and can be manufactured with a lower cost, but it can not provide a sufficient rigidity to support the socket assembly. A socket assembly 100′ shown in FIG. 1 includes a socket 1′ which electrically connect an semiconductor package 5′ to a PCB 3′, and a metal backplane 4′ is disposed on the backside of the PCB. The metal backplane 4′ has a high rigidity and can well properly support the PCB. However, the metal backplane 4′ must be insulated from the PCB to prevent short circuiting conductive traces of the PCB, an improved design is to dispose a soft insulative film (not shown) on a metal plane over a surface facing the PCB. The soft insulative film is attached to the metal plane by agglutinant to be integral backplane, then a plurality of screws are used to assemble the socket, the PCB, the soft insulative sheet and the metal plane to assemble them together.
Each of the soft insulative film and the metal plane defines a plurality of mounting holes for the screw passing there through. However, since the soft insulative sheet agglutinates to the metal plane, crimple airs and bladders may occur over the surface of the backplane, and it may takes time to align the mounting holes of the soft insulative sheet with that of the metal backplane. Furthermore, it is also not an easy thing to accurately position the insulative sheet together with the metal plane to the PCB for there is no positioning member between the insulative sheet and the PCB.
Hence, it is required to improve the disadvantages of the above sockets.